The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
William E Feeney - One of the best experts on this subject based on the ideXlab platform.
-
insights into the successful Breeding of hawksbill sea turtles eretmochelys imbricata from a long term Captive Breeding program
Global Ecology and Conservation, 2020Co-Authors: Ruth Maggeni, William E FeeneyAbstract:Abstract Sea turtle populations are declining and evidence-based methods for supporting their populations are required. Captive Breeding and release programs can be effective, offering the opportunity to supplement nature populations; however, sea turtles require specific conditions to successfully breed. Here, we present insights gained from a 12 year Hawksbill sea turtle (Eretmochelys imbricata) Captive Breeding program that was conducted at the Underwater Observatory Marine Park, Eilat, Israel, between 1982 and 1997. As the first program of its kind for the Hawksbill sea turtle, insights were gained largely through trial-and-error and advice from experienced individuals. The key insight gained during this program was the critical importance of pre-Breeding separation of the sexes; turtles did not breed prior to pre-Breeding separation being implemented, but it became predictably regular once it was. Over the course of the program, 161 two-three year old hatchlings were introduced to the Red Sea, which was enabled largely as a result of pre-Breeding separation being implemented.
-
insights into the successful Breeding of hawksbill sea turtles eretmochelys imbricata from a long term Captive Breeding program
bioRxiv, 2020Co-Authors: Ruth Maggeni, William E FeeneyAbstract:Abstract Sea turtle populations are declining and evidence-based methods for supporting their populations are required. Captive Breeding and release programs can be effective, offering the opportunity to supplement nature populations; however, sea turtles require specific conditions to successfully breed. Here, we present insights gained from a 16 year Hawksbill sea turtle (Eretmochelys imbricata) Captive Breeding program that was conducted at the Underwater Observatory Marine Park, Eilat, Israel, between 1982-1997. As the first program of its kind for the Hawksbill sea turtle, insights were gained largely through trial-and-error and word of mouth advice. The key insight gained during this program was the critical importance of pre-Breeding separation of the sexes; turtles did not breed prior to pre-Breeding separation being implemented, but it became predictably regular once it was. Over the course of the program, 161 two-three years old hatchlings were introduced to the Red Sea, which was enabled largely as a result of pre-Breeding separation being implemented.
Ruth Maggeni - One of the best experts on this subject based on the ideXlab platform.
-
insights into the successful Breeding of hawksbill sea turtles eretmochelys imbricata from a long term Captive Breeding program
Global Ecology and Conservation, 2020Co-Authors: Ruth Maggeni, William E FeeneyAbstract:Abstract Sea turtle populations are declining and evidence-based methods for supporting their populations are required. Captive Breeding and release programs can be effective, offering the opportunity to supplement nature populations; however, sea turtles require specific conditions to successfully breed. Here, we present insights gained from a 12 year Hawksbill sea turtle (Eretmochelys imbricata) Captive Breeding program that was conducted at the Underwater Observatory Marine Park, Eilat, Israel, between 1982 and 1997. As the first program of its kind for the Hawksbill sea turtle, insights were gained largely through trial-and-error and advice from experienced individuals. The key insight gained during this program was the critical importance of pre-Breeding separation of the sexes; turtles did not breed prior to pre-Breeding separation being implemented, but it became predictably regular once it was. Over the course of the program, 161 two-three year old hatchlings were introduced to the Red Sea, which was enabled largely as a result of pre-Breeding separation being implemented.
-
insights into the successful Breeding of hawksbill sea turtles eretmochelys imbricata from a long term Captive Breeding program
bioRxiv, 2020Co-Authors: Ruth Maggeni, William E FeeneyAbstract:Abstract Sea turtle populations are declining and evidence-based methods for supporting their populations are required. Captive Breeding and release programs can be effective, offering the opportunity to supplement nature populations; however, sea turtles require specific conditions to successfully breed. Here, we present insights gained from a 16 year Hawksbill sea turtle (Eretmochelys imbricata) Captive Breeding program that was conducted at the Underwater Observatory Marine Park, Eilat, Israel, between 1982-1997. As the first program of its kind for the Hawksbill sea turtle, insights were gained largely through trial-and-error and word of mouth advice. The key insight gained during this program was the critical importance of pre-Breeding separation of the sexes; turtles did not breed prior to pre-Breeding separation being implemented, but it became predictably regular once it was. Over the course of the program, 161 two-three years old hatchlings were introduced to the Red Sea, which was enabled largely as a result of pre-Breeding separation being implemented.
Ralph Kuehn - One of the best experts on this subject based on the ideXlab platform.
-
securing genetic integrity in freshwater pearl mussel propagation and Captive Breeding
Scientific Reports, 2021Co-Authors: Juergen Geist, Helmut Bayerl, Bernhard C Stoeckle, Ralph KuehnAbstract:Securing genetic integrity is of key importance in conservation-oriented Captive Breeding programs releasing juveniles into the wild. This is particularly true for species such as the endangered freshwater pearl mussel (Margaritifera margaritifera) for which a number of Captive Breeding facilities has been established in Europe. The core objective of this study was to compare the genetic constitution of 29 cohorts of Captive-bred freshwater pearl mussels from five different Breeding facilities in Austria, France, Luxembourg and Germany, with their original 14 source populations from nine major European drainages, based on microsatellite markers. Captive-bred mussels represented 11 different genetic clusters, suggesting an important contribution of the Breeding stations to securing the genetic diversity of the species. In almost all cases, the cultured offspring closely resembled the genetic constitution of the source mussels as revealed from the STRUCTURE analysis and the generally high assignment of offspring to the original source populations. The majority of Captive-bred cohorts had an increased inBreeding coefficient and decreased genetic variability compared to their source populations as measured by AR and HO. Highest numbers of deformed juveniles coincided with very low levels of HO < 0.05. Since erosion of genetic diversity in Captive Breeding was mostly evident in individual year-cohorts, long-term Breeding over multiple years can minimize such effects. The systematic selection of priority populations for conservation, effective Breeding strategies avoiding effects of in- and outBreeding by genetically informed selection of parent individuals, and a network of collaboration among the different Breeding facilities would be very useful to increase resilience and effectiveness.
Jeffrey A. Hutchings - One of the best experts on this subject based on the ideXlab platform.
-
risk assessment of inBreeding and outBreeding depression in a Captive Breeding program
Conservation Biology, 2014Co-Authors: Njal Rollinson, Aimee Lee S Houde, Dave M Keith, Meghan C Mcbride, P V Debes, Jeffrey A. HutchingsAbstract:Captive-Breeding programs can be implemented to preserve the genetic diversity of endangered populations such that the controlled release of Captive-bred individuals into the wild may promote recovery. A common difficulty, however, is that programs are founded with limited wild broodstock, and inBreeding can become increasingly difficult to avoid with successive generations in captivity. Program managers must choose between maintaining the genetic purity of populations, at the risk of inBreeding depression, or interBreeding populations, at the risk of outBreeding depression. We evaluate these relative risks in a Captive-Breeding program for 3 endangered populations of Atlantic salmon (Salmo salar). In each of 2 years, we released juvenile F1 and F2 interpopulation hybrids, backcrosses, as well as inbred and noninbred within-population crosstypes into 9 wild streams. Juvenile size and survival was quantified in each year. Few crosstype effects were observed, but interestingly, the relative fitness consequences of inBreeding and outBreeding varied from year to year. Temporal variation in environmental quality might have driven some of these annual differences, by exacerbating the importance of maternal effects on juvenile fitness in a year of low environmental quality and by affecting the severity of inBreeding depression differently in different years. Nonetheless, inBreeding was more consistently associated with a negative effect on fitness, whereas the consequences of outBreeding were less predictable. Considering the challenges associated with a sound risk assessment in the wild and given that the effect of inBreeding on fitness is relatively predictable, we suggest that risk can be weighted more strongly in terms of the probable outcome of outBreeding. Factors such as genetic similarities between populations and the number of generations in isolation can sometimes be used to assess outBreeding risk, in lieu of experimentation. Evaluacion del Riesgo de Depresion por Endogamia y Exogamia en un Programa de Reproduccion en Cautiverio Resumen Los programas de reproduccion en cautiverio pueden ser implementados para preservar la diversidad genetica de las poblaciones en peligro, de tal forma que la liberacion controlada de los individuos criados en cautiverio a la vida libre puede promover la recuperacion. Sin embargo, una dificultad comun es que los programas se encuentran dentro del limitado capital de reproduccion silvestre, y la endogamia puede volverse cada vez mas dificil de evitar con generaciones sucesivas en cautiverio. Los directores del programa deben elegir entre mantener la pureza genetica de las poblaciones, con el riesgo de una depresion endogamica, o reproducir entre poblaciones, con el riesgo de una depresion exogamica. Evaluamos estos riesgos relativos en un programa de reproduccion en cautiverio para tres poblaciones en peligro de salmon del Atlantico (Salmo salar). Cada 2 anos, liberamos juveniles hibridos inter-poblacionales F1 y F2, retrocruzamientos, asi como cruzas endogamicas y no endogamicas entre poblaciones en nueve arroyos silvestres. El tamano juvenil y la supervivencia se cuantificaron cada ano. Se observaron pocos efectos de cruza, pero interesantemente, las consecuencias de la adaptabilidad relativa de la endogamia y exogamia variaron ano con ano. La variacion temporal en la calidad ambiental pudo ser conductora en alguna de estas diferencias anuales, al exacerbar la importancia de los efectos maternales sobre la aptitud juvenil en un ano de baja calidad ambiental y al afectar diferentemente la severidad de la depresion endogamica en anos diferentes. Sin embargo, la endogamia fue asociada constantemente con un efecto negativo sobre la adaptabilidad, mientras que las consecuencias de la exogamia fueron menos predecibles. Considerando los obstaculos asociados con un estudio concreto de riesgo en vida silvestre y dado que el efecto de la endogamia sobre la aptitud es relativamente predecible, sugerimos que el riesgo puede considerarse mas fuerte en terminos de un resultado probable de la exogamia. Factores como las similitudes geneticas entre poblaciones y el numero de generaciones en aislamiento puede usarse algunas veces para estudiar el riesgo de la exogamia, en lugar de la experimentacion.
-
risk assessment of inBreeding and outBreeding depression in a Captive Breeding program
Conservation Biology, 2014Co-Authors: Njal Rollinson, Aimee Lee S Houde, Dave M Keith, Meghan C Mcbride, P V Debes, Jeffrey A. HutchingsAbstract:Captive-Breeding programs can be implemented to preserve the genetic diversity of endangered populations such that the controlled release of Captive-bred individuals into the wild may promote recovery. A common difficulty, however, is that programs are founded with limited wild broodstock, and inBreeding can become increasingly difficult to avoid with successive generations in captivity. Program managers must choose between maintaining the genetic purity of populations, at the risk of inBreeding depression, or interBreeding populations, at the risk of outBreeding depression. We evaluate these relative risks in a Captive-Breeding program for 3 endangered populations of Atlantic salmon (Salmo salar). In each of 2 years, we released juvenile F(1) and F(2) interpopulation hybrids, backcrosses, as well as inbred and noninbred within-population crosstypes into 9 wild streams. Juvenile size and survival was quantified in each year. Few crosstype effects were observed, but interestingly, the relative fitness consequences of inBreeding and outBreeding varied from year to year. Temporal variation in environmental quality might have driven some of these annual differences, by exacerbating the importance of maternal effects on juvenile fitness in a year of low environmental quality and by affecting the severity of inBreeding depression differently in different years. Nonetheless, inBreeding was more consistently associated with a negative effect on fitness, whereas the consequences of outBreeding were less predictable. Considering the challenges associated with a sound risk assessment in the wild and given that the effect of inBreeding on fitness is relatively predictable, we suggest that risk can be weighted more strongly in terms of the probable outcome of outBreeding. Factors such as genetic similarities between populations and the number of generations in isolation can sometimes be used to assess outBreeding risk, in lieu of experimentation.
Jarmo Koskiniemi - One of the best experts on this subject based on the ideXlab platform.
-
maintenance of genetic diversity of atlantic salmon salmo salar by Captive Breeding programmes and the geographic distribution of microsatellite variation
Aquaculture, 2002Co-Authors: Marjaliisa Koljonen, Jaana Tahtinen, Marjatta Saisa, Jarmo KoskiniemiAbstract:Abstract The capability of Finnish Atlantic salmon ( Salmo salar L.) broodstock Breeding programmes to maintain genetic diversity was assessed by comparing the levels of microsatellite diversity in wild and hatchery stocks in general, and in wild and hatchery derivatives of the same stock. The effective population sizes ( N e ) of the broodstocks and the ratio of effective size to census size ( N e / N c ) as well as the rate of loss of diversity in Captive Breeding were assessed. Moreover, the distribution and pattern of genetic diversity among Atlantic salmon stocks in the Baltic Sea, Barents Sea and NW Atlantic were measured. Microsatellite data were also compared with allozyme data of the same salmon stocks. Nine microsatellite loci were amplified: Ssa85, Ssa171, Ssa197, Ssa202, Ssa289, SSOSL85, SSOSL 311, SSOSL417 and SSOSL438 from 11 Atlantic salmon stocks. The effective population sizes of broodstocks were estimated with the method based on temporal allele frequency change. In short-term Breeding programmes, the average rate of loss of heterozygosity was 1.4% per generation and the average observed rate of loss of alleles was 4.7% per generation. The estimated N e 's for the broodstocks were 32 and 238. The average N e / N c ratio was 0.81. Changes in present-day broodstocks were not alarming and the N e / N c ratios were higher than in wild populations in general. The genetic D A distance between continents was 0.64 ( F ST ( θ )=0.22) and distances about half of that level ( D A distance 0.34, F ST =0.09) were measured between European and Baltic Sea salmon stocks. A nearly diagnostic difference was observed in the SSOSL311 of the North American stocks (Maine 0.982 and Labrador 0.957) for a single allele (SSOSL311 118 ) that did not occur in European populations at all. Microsatellite data showed relatively more genetic differentiation ( F ST =0.040) on a small geographical scale than did allozyme data ( F ST =0.017), indicating the higher discrimination power of this data set.